Bump mkdocs-material from 8.1.3 to 8.2.8 (#1564)

Bumps [mkdocs-material](https://github.com/squidfunk/mkdocs-material) from 8.1.3 to 8.2.8.
- [Release notes](https://github.com/squidfunk/mkdocs-material/releases)
- [Changelog](https://github.com/squidfunk/mkdocs-material/blob/master/CHANGELOG)
- [Commits](squidfunk/mkdocs-material@8.1.3...8.2.8)

---
updated-dependencies:
- dependency-name: mkdocs-material
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

requirements.txt

@@ -18,7 +18,7 @@ trio==0.19.0
 
 # Documentation
 mkdocs==1.3.0
-mkdocs-material==8.1.3
+mkdocs-material==8.2.8
 mkautodoc==0.1.0
 
 # Packaging